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Groupwise Study of Elements

This article deals with the study of elements and how they are classified into groups ,this article also briefs about the study of first element hydrogen.Finally,this article has the comparative study of elements.This article also briefs about the concept of grouping elements based on their properties and characterstics.

How to group the elements of the same characteristics? 

This requires the study of elements, requires the basic knowledge on understanding the characteristics of elements that belong to the same group. 

STUDY OF ELEMENTS:

For the study of elements, let’s consider some elements like aluminum, Iron, Copper, Silicon. These elements are grouped under certain categories like metals. semimetals, rare earths, and non-metals because of their characteristics. From the detailed study of elements, the elements are subdivided into groups based on their properties. 

Study of elements-First group:

The first group of elements in the periodic table is called ” alkali metals”.This group contain elements Hydrogen(H), Lithium(Li), Sodium(Na), Potassium (k), Rubidium (Ru), Caesium (Cs), Francium(Fr) 

Study of first element Hydrogen:

Overview:

The study of the first element revolves around the discovery of hydrogen and its atomic mass, atomic number, electronic configuration. Along with these, the study of first element hydrogen includes the Importance of hydrogen in various fields along with electronegativity. 

Discovery of Hydrogen:

The main topic of study of Hydrogen includes the discovery of Hydrogen by Henry Cavendish, but was initially identified by Robert Boyle and got named by Antonie Lavoisier in the year 1766.

  • The atomic number of Hydrogen is one and valency is one

  • The electronic configuration of hydrogen is 1s1

Study of first element Hydrogen- Properties and uses

  • Hydrogen is colourless, odourless as well as a non-poisonous gas. 

  • It is a diatomic molecule with chemical formula representation H2(two hydrogen atoms are combined to form a molecule) 

  • Hydrogen is highly flammable. 

  • It combines with oxygen to form the essential component known as water

  • It has a colour of pale blue when it burns

  • Applications and Uses:

  • Hydrogen is used in fuel cells 

  • Hydrogen is used in making fertilisers and pesticides

Group-wise understanding of the elements in First Group:

The metals of the first group Li, Na, K, Rb, Cs, Fr are metals with low ionisation energy. These metals are highly reactive. But these elements have low melting points. The alkali metals are easily ductile and malleable as the metals. These metals also conduct good electricity. The Elements Cs, Fr is highly reactive.

These elements can be easily cut and float on the water.

The chemical properties of group 1 elements with chemical equations 

2Li + 2H20 -> 2LiOH + H2

(Lithium) + water – Lithium hydroxide +Hydrogen

2Cs+ Cl2 ->2CsBr(s)

Caesium + chlorine -Caesium chloride

Likewise, in the above example of the 1st group elements, the other group elements also have almost all similar properties with the same valency hence they are made into the same groups. 

 Elements in the second group- basic properties:

The second group elements are called as alkaline earth metals,the metals in this group are beryllium,Magnesium,calcium,strontium,barium,radium.The main property of second group element is these are insoluble in water,these elements are unchangeable to fire,this difference is the main difference between alkali metals and alkali earth metals.

The Comparative study of elements in groups-13:

The following are the observations in the Comparative study of the elements in the same group

1) They have similar physical properties

2) They have almost equal chemical properties 

3) They have the same valency

4) They react the same with other elements

5)One group differs from other groups by the above properties

For example, let us have a look at a Comparative study of group 13 elements:

These are the p block elements. The following are the elements of the 13th block- ns2 np1

Boron,(B), Aluminum (Al), Gallium (Ga), Indium(In), and Thallium(Ti) 

They exhibit the Inert pair effect:

These metalloids satisfy the inert pair effect. The elements in this family have two types of valencies. The Comparative study on elements of p-block 13th block, oxidation states varies with +1 and +3 valencies. Here s orbital is not involved in the participation of chemical bonding. Hence causes an inert pair effect. 

These elements satisfy the covalent bonding along with high enthalpy. These elements have a higher electronegativity difference, high electronegativity with smaller size.

THE COMPARATIVE STUDY OF ELEMENTS (Between-group 13 and group 14)

There are many differences between 13th group and 14th group

  • The first one is valency and electronic configuration

  • The 13th group elements have the semi metals and metalloids where as the 14th group element have non-metals. 

  • Reaction with various elements

 Some of the elements react with the air to form respective oxides. 

All the group 13 elements react with halogens and trihalides.

Elements in 15th group- basic properties:

The group 15 elements belong to the nitrogen family.The elements of this family are nitrogen,phosphorus,Arsenic,Antimony,Bismuth.These elements exhibit wide variety of physical states.The first half part of this group are non-metals and the middle part are metalloids and last part are metals.These elements posses 5 electrons in their outer shell.

Elements in 16th group -basic properties:

The elements in 6th group are oxygen,sulphur,selenium,tellurium and polonium.These are named as chalcogens.For these elements only two electrons are necessary to become the octet.These elements are highly flammable and sulphur exhibits amorphous forms.

Elements in 17th group-basic properties:

The elements in the 7th group are called halogens.The elements in this group are fluorine,chlorine,bromine and iodine.These elements react with other elements and essentially forms salt.These elements lack one electron to become octet.

Elements in 18th group -basic properties:

These elements are inert gases that do not react with other elements,these are also called noble gases.Helium,Neon,Argon,Krypton,Xenon,Radon are the inert gases which have octa valency.

Conclusion:

From the demonstration and the comparative study of the elements group wise we can conclude that all the elements in the same group differ from each other. Comparatively the left side s block elements are metals the p-block elements are metalloids and nonmetals. The d block elements are transition metals. From the study of elements, we can conclude that various elements react with the other group elements differently.

faq

Frequently asked questions

Get answers to the most common queries related to the NDA Examination Preparation.

What is the difference between the elements in the groups?

Ans : Difference between groups is the valency of the elements. 

How can we classify the elements in a group?

Ans : If the elements have the same properties and valence electronic configuration  they can be ...Read full

Name the elements in the 13th group?

Ans : Boron, Indium, Aluminium, Gallium, Thallium are the 5 elements of the group and all these are...Read full